本實驗操作參數包括：湯種麵糰添加量(10%、20%、30%)、燙麵溫度(70 ℃、85 ℃、100 ℃)、熟成時間(0 hr、12 hr、24 hr)，探討操作參數對湯種麵糰發酵體積、土司體積、土司硬度值之影響。實驗結果發現，湯種麵糰添加量及燙麵溫度對麵糰發酵體積皆有極顯著性影響 (p < 0.01)，湯種麵糰熟成時間則無顯著影響 (p > 0.05)，湯種麵糰添加量、燙麵溫度及熟成時間之二次項均無顯著性影響，麵糰添加量及燙麵溫度之交互作用對於麵糰發酵體積有顯著性影響 (p < 0.05)。麵糰發酵體積迴歸模式之相關係數 R2=0.94，表示此迴歸模式對於麵糰發酵體積的解釋程度達 94%。在土司體積及硬度值方面，湯種麵糰添加量皆具有顯著性影響，而燙麵溫度及熟成時間則無顯著性影響。綜合各結果顯示，湯種土司以 10%湯種麵糰添加量，所製得之土司具有較大的體積及較低的硬度值，明顯增進土司柔軟度。

Boiled dough addition (10%, 20%, 30%), boiled dough temperature (70℃, 85℃, 100℃), and aging time (0 hr, 12 hr, 24 hr) were varied according to response surface methodology design. The effects on dough fermentation volume, bread loaf volume and hardness were investigated. It was noted that boiled dough addition and temperature significantly affected dough fermentation volume (p＜0.01). However, boiled dough aging time had no significant affect (p＞0.05). The correlation coefficient (R2) was 0.94, which shows that the experimental values of dough fermentation volume are relatively consistent with predicted values.Boiled dough addition significantly affected bread loaf volume and hardness, whereas boiled dough temperature and aging time had no significant effect. Our results showed that the dough with 10% boiled dough addition had higher bread loaf volume and lower crumb hardness.